Just imagine how easy things would have been if these 3000$+ computers had the necessary ports built into them.

That would only solve some problems. My typical problem of not wanting to wire up 6 or 7 cables every time I switch between home-office and office would still go unsolved. Just plugging in a hub that already has keyboard, mouse, headset, monitors, and preferably even power attached is very nice to be actually flexible with the setup (also when quickly moving to a conference room and back).